9975987 has 16 divisors (see below), whose sum is σ = 16890880. Its totient is φ = 5700456.

The previous prime is 9975943. The next prime is 9975989. The reversal of 9975987 is 7895799.

It is a de Polignac number, because none of the positive numbers 2^k-9975987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9975989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26203 + ... + 26580.

It is an arithmetic number, because the mean of its divisors is an integer number (1055680).

Almost surely, 2^9975987 is an apocalyptic number.

9975987 is a deficient number, since it is larger than the sum of its proper divisors (6914893).

9975987 is a wasteful number, since it uses less digits than its factorization.

9975987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52799 (or 52793 counting only the distinct ones).

The product of its digits is 1428840, while the sum is 54.

The square root of 9975987 is about 3158.4785894478. The cubic root of 9975987 is about 215.2708826515.

The spelling of 9975987 in words is "nine million, nine hundred seventy-five thousand, nine hundred eighty-seven".